<?php if (!defined('BASEPATH')) exit('No direct script access allowed');

/**
 * Ignited Datatables
 *
 * This is a wrapper class/library based on the native Datatables server-side implementation by Allan Jardine
 * found at http://datatables.net/examples/data_sources/server_side.html for CodeIgniter
 *
 * @package    CodeIgniter
 * @subpackage libraries
 * @category   library
 * @version    2.0 <beta>
 * @author     Vincent Bambico <metal.conspiracy@gmail.com>
 *             Yusuf Ozdemir <yusuf@ozdemir.be>
 * @link       http://ellislab.com/forums/viewthread/160896/
 */
class Datatables {
    /**
     * Global container variables for chained argument results
     *
     */
    private $ci;
    private $table;
    private $distinct;
    private $group_by = array();
    private $select = array();
    private $joins = array();
    private $columns = array();
    private $where = array();
    private $or_where = array();
    private $where_in = array();
    private $like = array();
    private $or_like = array();
    private $filter = array();
    private $add_columns = array();
    private $edit_columns = array();
    private $unset_columns = array();

    /**
     * Copies an instance of CI
     */
    public function __construct() {
        $this->ci =& get_instance();
    }

    /**
     * If you establish multiple databases in config/database.php this will allow you to
     * set the database (other than $active_group) - more info: http://ellislab.com/forums/viewthread/145901/#712942
     */
    public function set_database($db_name) {
        $db_data = $this->ci->load->database($db_name, TRUE);
        $this->ci->db = $db_data;
    }

    /**
     * Generates the SELECT portion of the query
     *
     * @param string $columns
     * @param bool $backtick_protect
     * @return mixed
     */
    public function select($columns, $backtick_protect = TRUE) {
        foreach ($this->explode(',', $columns) as $val) {
            $column = trim(preg_replace('/(.*)\s+as\s+(\w*)/i', '$2', $val));
            $column = preg_replace('/.*\.(.*)/i', '$1', $column); // get name after `.`
            $this->columns[] = $column;
            $this->select[$column] = trim(preg_replace('/(.*)\s+as\s+(\w*)/i', '$1', $val));
        }
        $this->ci->db->select($columns, $backtick_protect);
        return $this;
    }

    /**
     * Generates the DISTINCT portion of the query
     *
     * @param string $column
     * @return mixed
     */
    public function distinct($column) {
        $this->distinct = $column;
        $this->ci->db->distinct($column);
        return $this;
    }

    /**
     * Generates a custom GROUP BY portion of the query
     *
     * @param string $val
     * @return mixed
     */
    public function group_by($val) {
        $this->group_by[] = $val;
        $this->ci->db->group_by($val);
        return $this;
    }


    /**
     * Generates the FROM portion of the query
     *
     * @param string $table
     * @return mixed
     */
    public function from($table) {
        $this->table = $table;
        return $this;
    }

    /**
     * Generates the JOIN portion of the query
     *
     * @param string $table
     * @param string $fk
     * @param string $type
     * @return mixed
     */
    public function join($table, $fk, $type = NULL) {
        $this->joins[] = array($table, $fk, $type);
        $this->ci->db->join($table, $fk, $type);
        return $this;
    }

    public function order_by($order, $asc='ASC') {
        $this->ci->db->order_by($order,$asc);
        return $this;
    }

    /**
     * Generates the WHERE portion of the query
     *
     * @param mixed $key_condition
     * @param string $val
     * @param bool $backtick_protect
     * @return mixed
     */
    public function where($key_condition, $val = NULL, $backtick_protect = TRUE) {
        $this->where[] = array($key_condition, $val, $backtick_protect);
        $this->ci->db->where($key_condition, $val, $backtick_protect);
        return $this;
    }

    /**
     * Generates the WHERE portion of the query
     *
     * @param mixed $key_condition
     * @param string $val
     * @param bool $backtick_protect
     * @return mixed
     */
    public function or_where($key_condition, $val = NULL, $backtick_protect = TRUE) {
        $this->or_where[] = array($key_condition, $val, $backtick_protect);
        $this->ci->db->or_where($key_condition, $val, $backtick_protect);
        return $this;
    }

    /**
     * Generates the WHERE IN portion of the query
     *
     * @param mixed $key_condition
     * @param string $val
     * @param bool $backtick_protect
     * @return mixed
     */
    public function where_in($key_condition, $val = NULL) {
        $this->where_in[] = array($key_condition, $val);
        $this->ci->db->where_in($key_condition, $val);
        return $this;
    }

    /**
     * Generates the WHERE portion of the query
     *
     * @param mixed $key_condition
     * @param string $val
     * @param bool $backtick_protect
     * @return mixed
     */
    public function filter($key_condition, $val = NULL, $backtick_protect = TRUE) {
        $this->filter[] = array($key_condition, $val, $backtick_protect);
        return $this;
    }

    /**
     * Generates a %LIKE% portion of the query
     *
     * @param mixed $key_condition
     * @param string $val
     * @param bool $backtick_protect
     * @return mixed
     */
    public function like($key_condition, $val = NULL, $side = 'both') {
        $this->like[] = array($key_condition, $val, $side);
        $this->ci->db->like($key_condition, $val, $side);
        return $this;
    }

    /**
     * Generates the OR %LIKE% portion of the query
     *
     * @param mixed $key_condition
     * @param string $val
     * @param bool $backtick_protect
     * @return mixed
     */
    public function or_like($key_condition, $val = NULL, $side = 'both') {
        $this->or_like[] = array($key_condition, $val, $side);
        $this->ci->db->or_like($key_condition, $val, $side);
        return $this;
    }

    /**
     * Sets additional column variables for adding custom columns
     *
     * @param string $column
     * @param string $content
     * @param string $match_replacement
     * @return mixed
     */
    public function add_column($column, $content, $match_replacement = NULL) {
        $this->add_columns[$column] = array(
            'content' => $content, 'replacement' => $this->explode(',', $match_replacement)
        );
        return $this;
    }

    /**
     * Sets additional column variables for editing columns
     *
     * @param string $column
     * @param string $content
     * @param string $match_replacement
     * @return mixed
     */
    public function edit_column($column, $content, $match_replacement) {
        $this->edit_columns[$column][] = array(
            'content' => $content, 'replacement' => $this->explode(',', $match_replacement)
        );
        return $this;
    }

    /**
     * Unset column
     *
     * @param string $column
     * @return mixed
     */
    public function unset_column($column) {
        $column = explode(',', $column);
        $this->unset_columns = array_merge($this->unset_columns, $column);
        return $this;
    }

    /**
     * Builds all the necessary query segments and performs the main query based on results set from chained statements
     *
     * @param string $output
     * @param string $charset
     * @return string
     */
    public function generate($output = 'json', $charset = 'UTF-8') {
        if (strtolower($output) == 'json') $this->get_paging();
        $this->get_ordering();
        //$this->get_filtering();
        return $this->produce_output(strtolower($output), strtolower($charset));
    }

    /**
     * Generates the LIMIT portion of the query
     *
     * @return mixed
     */
    private function get_paging() {
        $iStart = $this->ci->input->post_get('start');
        $iLength = $this->ci->input->post_get('length');
        if ($iLength != '' && $iLength != '-1') $this->ci->db->limit($iLength, ($iStart) ? $iStart : 0);
    }

    /**
     * Generates the ORDER BY portion of the query
     *
     * @return mixed
     */
    private function get_ordering() {
        $Data = $this->ci->input->post_get('columns');
        if ($this->ci->input->post_get('order')) foreach ($this->ci->input->post_get('order') as $key) if ($this->check_cType()) $this->ci->db->order_by($Data[$key['column']]['data'], $key['dir']); else
            $this->ci->db->order_by($this->columns[$key['column']], $key['dir']);
    }

    /**
     * Generates a %LIKE% portion of the query
     *
     * @return mixed
     */
    private function get_filtering() {
        $mColArray = $this->ci->input->post_get('columns');
        $sWhere = '';
        $search = $this->ci->input->post_get('search');
        $sSearch = $this->ci->db->escape_like_str(trim($search['value']));
        $columns = array_values(array_diff($this->columns, $this->unset_columns));
        if ($sSearch != '') for ($i = 0; $i < count($mColArray); $i++) if ($mColArray[$i]['searchable'] == 'true' && !array_key_exists($mColArray[$i]['data'], $this->add_columns)) if ($this->check_cType()) $sWhere .= $this->select[$mColArray[$i]['data']] . " LIKE '%" . $sSearch . "%' OR "; else
            $sWhere .= $this->select[$this->columns[$i]] . " LIKE '%" . $sSearch . "%' OR ";
        $sWhere = substr_replace($sWhere, '', -3);
        if ($sWhere != '') $this->ci->db->where('(' . $sWhere . ')');
        // TODO : sRangeSeparator
        foreach ($this->filter as $val) $this->ci->db->where($val[0], $val[1], $val[2]);
    }

    /**
     * Compiles the select statement based on the other functions called and runs the query
     *
     * @return mixed
     */
    private function get_display_result() {
        return $this->ci->db->get($this->table);
    }

    /**
     * Builds an encoded string data. Returns JSON by default, and an array of aaData if output is set to raw.
     *
     * @param string $output
     * @param string $charset
     * @return mixed
     */
    private function produce_output($output, $charset) {
        $aaData = array();
        $rResult = $this->get_display_result();
        if ($output == 'json') {
            $iTotal = $this->get_total_results();
            $iFilteredTotal = $this->get_total_results(false);
        }
        foreach ($rResult->result_array() as $row_key => $row_val) {
            $aaData[$row_key] = ($this->check_cType()) ? $row_val : array_values($row_val);
            foreach ($this->add_columns as $field => $val) if ($this->check_cType()) $aaData[$row_key][$field] = $this->exec_replace($val, $aaData[$row_key]); else
                $aaData[$row_key][] = $this->exec_replace($val, $aaData[$row_key]);
            foreach ($this->edit_columns as $modkey => $modval) foreach ($modval as $val) $aaData[$row_key][($this->check_cType()) ? $modkey : array_search($modkey, $this->columns)] = $this->exec_replace($val, $aaData[$row_key]);
            $aaData[$row_key] = array_diff_key($aaData[$row_key], ($this->check_cType()) ? $this->unset_columns : array_intersect($this->columns, $this->unset_columns));
            if (!$this->check_cType()) $aaData[$row_key] = array_values($aaData[$row_key]);
        }
        if ($output == 'json') {
            $sOutput = array(
                'draw' => intval($this->ci->input->post_get('draw')), 'recordsTotal' => $iTotal,
                'recordsFiltered' => $iFilteredTotal, 'data' => $aaData
            );
            if ($charset == 'utf-8') return json_encode($sOutput); else
                return $this->jsonify($sOutput);
        } else
            return array('aaData' => $aaData);
    }

    /**
     * Get result count
     *
     * @return integer
     */
    private function get_total_results($filtering = FALSE) {
        if ($filtering) $this->get_filtering();
        foreach ($this->joins as $val) $this->ci->db->join($val[0], $val[1], $val[2]);
        foreach ($this->where as $val) $this->ci->db->where($val[0], $val[1], $val[2]);
        foreach ($this->or_where as $val) $this->ci->db->or_where($val[0], $val[1], $val[2]);

        foreach ($this->where_in as $val) $this->ci->db->where_in($val[0], $val[1]);
        foreach ($this->group_by as $val) $this->ci->db->group_by($val);
        foreach ($this->like as $val) $this->ci->db->like($val[0], $val[1], $val[2]);
        foreach ($this->or_like as $val) $this->ci->db->or_like($val[0], $val[1], $val[2]);
        if (strlen($this->distinct) > 0) {
            $this->ci->db->distinct($this->distinct);
            $this->ci->db->select($this->columns);
        }
        $query = $this->ci->db->get($this->table, NULL, NULL, FALSE);
        return $query->num_rows();
    }

    /**
     * Runs callback functions and makes replacements
     *
     * @param mixed $custom_val
     * @param mixed $row_data
     * @return string $custom_val['content']
     */
    private function exec_replace($custom_val, $row_data) {
        $replace_string = '';

        // Go through our array backwards, else $1 (foo) will replace $11, $12 etc with foo1, foo2 etc
        $custom_val['replacement'] = array_reverse($custom_val['replacement'], true);
        if (isset($custom_val['replacement']) && is_array($custom_val['replacement'])) {
            //Added this line because when the replacement has over 10 elements replaced the variable "$1" first by the "$10"
            $custom_val['replacement'] = array_reverse($custom_val['replacement'], true);
            foreach ($custom_val['replacement'] as $key => $val) {
                $sval = preg_replace("/(?<!\w)([\'\"])(.*)\\1(?!\w)/i", '$2', trim($val));
                if (preg_match('/(\w+::\w+|\w+)\((.*)\)/i', $val, $matches) && is_callable($matches[1])) {
                    $func = $matches[1];
                    $args = preg_split("/[\s,]*\\\"([^\\\"]+)\\\"[\s,]*|" . "[\s,]*'([^']+)'[\s,]*|" . "[,]+/", $matches[2], 0, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
                    foreach ($args as $args_key => $args_val) {
                        $args_val = preg_replace("/(?<!\w)([\'\"])(.*)\\1(?!\w)/i", '$2', trim($args_val));
                        $args[$args_key] = (in_array($args_val, $this->columns)) ? ($row_data[($this->check_cType()) ? $args_val : array_search($args_val, $this->columns)]) : $args_val;
                    }
                    $replace_string = call_user_func_array($func, $args);
                } elseif (in_array($sval, $this->columns)) $replace_string = $row_data[($this->check_cType()) ? $sval : array_search($sval, $this->columns)];
                else
                    $replace_string = $sval;
                $custom_val['content'] = str_ireplace('$' . ($key + 1), $replace_string, $custom_val['content']);
            }
        }
        return $custom_val['content'];
    }

    /**
     * Check column type -numeric or column name
     *
     * @return bool
     */
    private function check_cType() {
        $column = $this->ci->input->post_get('columns');
        if (is_numeric($column[0]['data'])) return FALSE; else
            return TRUE;
    }

    /**
     * Return the difference of open and close characters
     *
     * @param string $str
     * @param string $open
     * @param string $close
     * @return string $retval
     */
    private function balanceChars($str, $open, $close) {
        $openCount = substr_count($str, $open);
        $closeCount = substr_count($str, $close);
        $retval = $openCount - $closeCount;
        return $retval;
    }

    /**
     * Explode, but ignore delimiter until closing characters are found
     *
     * @param string $delimiter
     * @param string $str
     * @param string $open
     * @param string $close
     * @return mixed $retval
     */
    private function explode($delimiter, $str, $open = '(', $close = ')') {
        $retval = array();
        $hold = array();
        $balance = 0;
        $parts = explode($delimiter, $str);
        foreach ($parts as $part) {
            $hold[] = $part;
            $balance += $this->balanceChars($part, $open, $close);
            if ($balance < 1) {
                $retval[] = implode($delimiter, $hold);
                $hold = array();
                $balance = 0;
            }
        }
        if (count($hold) > 0) $retval[] = implode($delimiter, $hold);
        return $retval;
    }

    /**
     * Workaround for json_encode's UTF-8 encoding if a different charset needs to be used
     *
     * @param mixed $result
     * @return string
     */
    private function jsonify($result = FALSE) {
        if (is_null($result)) return 'null';
        if ($result === FALSE) return 'false';
        if ($result === TRUE) return 'true';
        if (is_scalar($result)) {
            if (is_float($result)) return floatval(str_replace(',', '.', strval($result)));
            if (is_string($result)) {
                static $jsonReplaces = array(
                    array('\\', '/', '\n', '\t', '\r', '\b', '\f', '"'),
                    array('\\\\', '\\/', '\\n', '\\t', '\\r', '\\b', '\\f', '\"')
                );
                return '"' . str_replace($jsonReplaces[0], $jsonReplaces[1], $result) . '"';
            } else
                return $result;
        }
        $isList = TRUE;
        for ($i = 0, reset($result); $i < count($result); $i++, next($result)) {
            if (key($result) !== $i) {
                $isList = FALSE;
                break;
            }
        }
        $json = array();
        if ($isList) {
            foreach ($result as $value) $json[] = $this->jsonify($value);
            return '[' . join(',', $json) . ']';
        } else {
            foreach ($result as $key => $value) $json[] = $this->jsonify($key) . ':' . $this->jsonify($value);
            return '{' . join(',', $json) . '}';
        }
    }

    /**
     * returns the sql statement of the last query run
     * @return type
     */
    public function last_query() {
        return $this->ci->db->last_query();
    }
}
/* End of file Datatables.php */
/* Location: ./application/libraries/Datatables.php */